Foraminifera and calcareous nannoplankton from the "Rzehakia (Oncophora) Beds" in the Central Paratethys

Foraminiferal and calcareous nannoplankton assemblages in the "Rzehakia (On cophora) Beds" from the Slovak and Hungarian part of the Nograd Basin and f rom the Upper Austrian Molasse were studied in detail including quantitativ e and taphonomical analyses. Foraminiferal assemblages are composed of a hi gh percentage of suspension-transported tests and rare indigenous shallow-w ater, predominantly euryhaline species. Two source areas of suspension-tran sported tests were interpreted for the Nograd Basin and the Upper Austrian Molasse. The discrepancy in the transgressive (Alpine Foredeep) vs. regressive chara cter (other areas) of the "Rzehakia (Oncophora) Beds" is caused by tectonic events at the Ottnangian/Karpatian boundary. The "Rzehakia (Oncophora) Bed s" in the Central Paratethys represent a separate cycle which may be well c orrelated with the upper Ottnangian. Its isochroneity is interpreted from c limatic events marked by abundant occurrences of suspension-transported tes ts and tempestites. The coexistence of two marine connections in the interv al corresponding to the "Rzehakia (Oncophora) Beds" is impliced: 1. "old" s eaway connecting the Alpine Foredeep with the Nograd Basin through shallow- water, partly brackish basins (Upper Austrian Molasse - Carpathian Foredeep - northern part of Vienna Basin - northern part of Danube Basin - southern Slovakia); 2. "new" sea-way through the "Trans-Tethyan Trench Corridor".